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The 13C-NMR Features of Natural Taxane Diterpenoid Compounds


The paper reviewed the 13C-NMR features of natural taxane diterpenoids according to their carbon-skeleton types. In the 13C-NMR it is easy to distinguish the 6/8/6 and 5/7/6 membered rings by observation of the 13C-NMR data of C-1 and C-15. The remarkable differences of the resonance of C -13 and C-12 were found. In addition, based on various chemical environments man y obscured chemical shifts of carbons can be distinguished, such as the oxygenat ed tertiary carbons of C-2, C-5, C-7, C-9 and C-13, and sometimes between C-9 an d C-10, as well as between aliphatic quaternary carbons of C-8 and C-15, and sec ondary carbons of C-6 and C-14. All the above-mentioned characteristics are helpful for structural elucidation and assignments of the carbon signals of taxoids.


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